this source, which tells me that I missed quite a lot. Apparently, this issue finally continues the aborted story of Dr. Mystic from Centaur's Comics Magazine #1. According to Mike,
"Dr. Occult and Zator visit the realm of the Seven. On the journey, they are attacked by the ether entities of Koth. After a mental duel, Dr. Occult prevails and reaches the Seven. He is then given a magic sword and sent on a quest to obtain a magic belt that can defeat Koth. Occult and Zator then travel to an Egyptian tomb where the belt is hidden."
I have speculated previously as to the nature of those "ether entities". The magic sword apparently grants Dr. Occult the abilities of a 1st-level Superhero, because he dawns a costume and exhibits superhuman strength while wielding it (and foreshadowing the coming of Superman from the same creative team nearly two years later). Mike also says that the sword is a Sword of Dancing, able to attack on its own while leaving Occult's hands free for other things.
An Egyptian tomb makes a swell hideout for a fantasy-/mythology-themed scenario. And a quest for a magic belt makes as good a plot hook as any. Still don't know what the magic belt is supposed to do, though!